source/passdb/machine_sid.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Password and authentication handling
   4    Copyright (C) Jeremy Allison                 1996-2002
   5    Copyright (C) Andrew Tridgell                2002
   6    Copyright (C) Gerald (Jerry) Carter          2000
   7    Copyright (C) Stefan (metze) Metzmacher      2002
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 */
  23
  24 #include "includes.h"
  25
  26 /* NOTE! the global_sam_sid is the SID of our local SAM. This is only
  27    equal to the domain SID when we are a DC, otherwise its our
  28    workstation SID */
  29 static DOM_SID *global_sam_sid=NULL;
  30
  31 #undef DBGC_CLASS
  32 #define DBGC_CLASS DBGC_PASSDB
  33
  34 /****************************************************************************
  35  Read a SID from a file. This is for compatibility with the old MACHINE.SID
  36  style of SID storage
  37 ****************************************************************************/
  38
  39 static BOOL read_sid_from_file(const char *fname, DOM_SID *sid)
  40 {
  41         char **lines;
  42         int numlines;
  43         BOOL ret;
  44
  45         lines = file_lines_load(fname, &numlines,0);
  46
  47         if (!lines || numlines < 1) {
  48                 if (lines) file_lines_free(lines);
  49                 return False;
  50         }
  51
  52         ret = string_to_sid(sid, lines[0]);
  53         file_lines_free(lines);
  54         return ret;
  55 }
  56
  57 /*
  58   generate a random sid - used to build our own sid if we don't have one
  59 */
  60 static void generate_random_sid(DOM_SID *sid)
  61 {
  62         int i;
  63         uchar raw_sid_data[12];
  64
  65         memset((char *)sid, '\0', sizeof(*sid));
  66         sid->sid_rev_num = 1;
  67         sid->id_auth[5] = 5;
  68         sid->num_auths = 0;
  69         sid->sub_auths[sid->num_auths++] = 21;
  70
  71         generate_random_buffer(raw_sid_data, 12);
  72         for (i = 0; i < 3; i++)
  73                 sid->sub_auths[sid->num_auths++] = IVAL(raw_sid_data, i*4);
  74 }
  75
  76 /****************************************************************************
  77  Generate the global machine sid.
  78 ****************************************************************************/
  79
  80 static DOM_SID *pdb_generate_sam_sid(void)
  81 {
  82         DOM_SID domain_sid;
  83         char *fname = NULL;
  84         DOM_SID *sam_sid;
  85
  86         if(!(sam_sid=SMB_MALLOC_P(DOM_SID)))
  87                 return NULL;
  88
  89         if ( IS_DC ) {
  90                 if (secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
  91                         sid_copy(sam_sid, &domain_sid);
  92                         return sam_sid;
  93                 }
  94         }
  95
  96         if (secrets_fetch_domain_sid(global_myname(), sam_sid)) {
  97
  98                 /* We got our sid. If not a pdc/bdc, we're done. */
  99                 if ( !IS_DC )
 100                         return sam_sid;
 101
 102                 if (!secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
 103
 104                         /* No domain sid and we're a pdc/bdc. Store it */
 105
 106                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 107                                 DEBUG(0,("pdb_generate_sam_sid: Can't store domain SID as a pdc/bdc.\n"));
 108                                 SAFE_FREE(sam_sid);
 109                                 return NULL;
 110                         }
 111                         return sam_sid;
 112                 }
 113
 114                 if (!sid_equal(&domain_sid, sam_sid)) {
 115
 116                         /* Domain name sid doesn't match global sam sid. Re-store domain sid as 'local' sid. */
 117
 118                         DEBUG(0,("pdb_generate_sam_sid: Mismatched SIDs as a pdc/bdc.\n"));
 119                         if (!secrets_store_domain_sid(global_myname(), &domain_sid)) {
 120                                 DEBUG(0,("pdb_generate_sam_sid: Can't re-store domain SID for local sid as PDC/BDC.\n"));
 121                                 SAFE_FREE(sam_sid);
 122                                 return NULL;
 123                         }
 124                         return sam_sid;
 125                 }
 126
 127                 return sam_sid;
 128
 129         }
 130
 131         /* check for an old MACHINE.SID file for backwards compatibility */
 132         asprintf(&fname, "%s/MACHINE.SID", lp_private_dir());
 133
 134         if (read_sid_from_file(fname, sam_sid)) {
 135                 /* remember it for future reference and unlink the old MACHINE.SID */
 136                 if (!secrets_store_domain_sid(global_myname(), sam_sid)) {
 137                         DEBUG(0,("pdb_generate_sam_sid: Failed to store SID from file.\n"));
 138                         SAFE_FREE(fname);
 139                         SAFE_FREE(sam_sid);
 140                         return NULL;
 141                 }
 142                 unlink(fname);
 143                 if ( !IS_DC ) {
 144                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 145                                 DEBUG(0,("pdb_generate_sam_sid: Failed to store domain SID from file.\n"));
 146                                 SAFE_FREE(fname);
 147                                 SAFE_FREE(sam_sid);
 148                                 return NULL;
 149                         }
 150                 }
 151
 152                 /* Stored the old sid from MACHINE.SID successfully.*/
 153                 SAFE_FREE(fname);
 154                 return sam_sid;
 155         }
 156
 157         SAFE_FREE(fname);
 158
 159         /* we don't have the SID in secrets.tdb, we will need to
 160            generate one and save it */
 161         generate_random_sid(sam_sid);
 162
 163         if (!secrets_store_domain_sid(global_myname(), sam_sid)) {
 164                 DEBUG(0,("pdb_generate_sam_sid: Failed to store generated machine SID.\n"));
 165                 SAFE_FREE(sam_sid);
 166                 return NULL;
 167         }
 168         if ( IS_DC ) {
 169                 if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 170                         DEBUG(0,("pdb_generate_sam_sid: Failed to store generated domain SID.\n"));
 171                         SAFE_FREE(sam_sid);
 172                         return NULL;
 173                 }
 174         }
 175
 176         return sam_sid;
 177 }
 178
 179 /* return our global_sam_sid */
 180 DOM_SID *get_global_sam_sid(void)
 181 {
 182         if (global_sam_sid != NULL)
 183                 return global_sam_sid;
 184
 185         /* memory for global_sam_sid is allocated in
 186            pdb_generate_sam_sid() as needed */
 187
 188         if (!(global_sam_sid = pdb_generate_sam_sid())) {
 189                 smb_panic("Could not generate a machine SID\n");
 190         }
 191
 192         return global_sam_sid;
 193 }
 194
 195 /**
 196  * Force get_global_sam_sid to requery the backends
 197  */
 198 void reset_global_sam_sid(void)
 199 {
 200         SAFE_FREE(global_sam_sid);
 201 }
 202
 203 /*****************************************************************
 204  Check if the SID is our domain SID (S-1-5-21-x-y-z).
 205 *****************************************************************/
 206
 207 BOOL sid_check_is_domain(const DOM_SID *sid)
 208 {
 209         return sid_equal(sid, get_global_sam_sid());
 210 }
 211
 212 /*****************************************************************
 213  Check if the SID is our domain SID (S-1-5-21-x-y-z).
 214 *****************************************************************/
 215
 216 BOOL sid_check_is_in_our_domain(const DOM_SID *sid)
 217 {
 218         DOM_SID dom_sid;
 219         uint32 rid;
 220
 221         sid_copy(&dom_sid, sid);
 222         sid_split_rid(&dom_sid, &rid);
 223
 224         return sid_equal(&dom_sid, get_global_sam_sid());
 225 }